Dingell lauds EPA for evaluating toxic chemical

U.S. Rep. Debbie Dingell is praising the Environmental Protection Agency for its decision to evaluate the toxic chemical 1,4-dioxane, which was detected in shallow groundwater in Ann Arbor.

The EPA announced that 1,4-dioxane will be among the first 10 chemicals it looks at under reforms to the Toxic Substances Control Act.

Dingell on Tuesday said it was "critical" for the agency to assess the chemical for its potential risk to humans and the environment.

"The growing dioxane plume that has been spreading through Ann Arbor’s groundwater for decades poses a potential threat to our families and the community, and this announcement from EPA will help give us new tools to deal with this decades-old problem," Dingell said in a statement Tuesday.

Michigan Department of Environmental Quality officials said the concentrations of 1,4 dioxane were about 2 parts per billion to 3 parts per billion, below the department’s precautionary screening levels for risk of vapor intrusion into buildings.

Officials said there was no public health risk.

Critics said the discovery in shallow groundwater of the toxic chemical in a dense neighborhood had a chance of human exposure.

Dingell said it was significant that 1,4-dioxane was among the 10 chemicals that EPA chose to evaluate.

"EPA must complete a risk evaluation of dioxane and the other nine chemicals within three years to determine whether they present a risk to humans and the environment," Dingell said. "If it is determined that a chemical presents an unreasonable risk, EPA must mitigate that risk within two years."

Dioxane affects the central nervous system, kidney and liver, and is classified as “possibly carcinogenic to humans,” according to the Centers for Disease Control and Prevention.

Suspected carcinogen 1,4-Dioxane was recently detected in shallow groundwater near Ann Arbor’s Waterworks Park and Slauson Middle School on the city’s west side. That’s more than two miles from the former site of Gelman Sciences Inc. and its follower, Pall Life Sciences, where the original contamination is believed to have occurred.